A novel palladium-catalyzed [2 + 2 + 1] annulation of alkyne-tethered aryl iodides with diaziridinone was developed, leading to the formation of 3,4-fused tricyclic indoles. From a mechanistic standpoint, the formation of fused tricyclic indole scaffolds involved ,-palladacycles, which were synthesized through the intramolecular reaction of aryl halides and alkynes. The cascade reaction described herein could be carried out with a broad range of substrates and provided various 3,4-fused tricyclic indoles with yields up to 98%.
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RSC Adv
January 2025
Department of Organic Chemistry, University of Debrecen Egyetem Square 1 Debrecen 4032 Hungary
Domino Knoevenagel-cyclization reactions of styrene substrates, containing an -(-formyl)aryl subunit, were carried out with -substituted 2-cyanoacetamides to prepare tetrahydro-4-pyrano[3,4-]quinolone and hexahydrobenzo[]phenanthridine derivatives by competing IMHDA and IMSDA cyclization, respectively. The diastereoselective IMHDA step with α,β-unsaturated amide, thioamide, ester and ketone subunits as a heterodiene produced condensed chiral tetrahydropyran or thiopyran derivatives, which in the case of Meldrum's acid were reacted further with amine nucleophiles in a multistep domino sequence. In order to simplify the benzene-condensed tricyclic core of the targets and get access to hexahydro-1-pyrano[3,4-]pyridine derivatives, a truncated substrate was reacted with cyclic and acyclic active methylene reagents in diastereoselective Knoevenagel-IMHDA reactions to prepare novel condensed heterocyclic scaffolds.
View Article and Find Full Text PDFPhytochemistry
January 2025
Institute of Clinical Medical Sciences & Department of Pharmacy, China-Japan Friendship Hospital, Beijing, 100029, China. Electronic address:
Daphnane diterpenoids, as one of the representative types of diterpenoid compounds with rich structural diversity and significant biological activities, have an uncommon 5/7/6 tricyclic skeleton mainly found in species of Thymelaeaceae and Euphorbiaceae families. Due to the unique peculiarity of the framework and remarkable pharmacological activities, over the past three decades, novel structures have been continuously discovered and more structural subtypes have been derived. However, there is always a lack of a unified and convincing structural classification strategy for the summary of daphnane diterpenoids, which affects the in-depth and systematic research of pharmaceutical chemists and pharmacologists.
View Article and Find Full Text PDFFunctional dyspepsia (FD) is a gut-brain axis disorder characterized by postprandial fullness, early satiety, bloating and/or epigastric pain, which are presumed to originate in the gastroduodenal tract. While the international recommendations in the Rome IV consensus require endoscopy to rule out an organic condition before establishing a diagnosis of FD, international guidelines recommend that, in the absence of risk factors, patient management be initiated at the primary care level by establishing Helicobacter pylori infection status, with eradication when positive, followed by empiric therapy with proton pump inhibitors and/or prokinetics, and that endoscopy be reserved for patients refractory to said measures. Second-line therapy includes neuromodulating agents, among which tricyclic antidepressants and atypical antipsychotics such as levosulpiride stand out.
View Article and Find Full Text PDFBMC Prim Care
January 2025
Département des sciences de la santé, Université du Québec en Abitibi-Témiscamingue (UQAT), Rouyn-Noranda, Québec, Canada.
Background: The risks associated with medications and co-medications for chronic pain (CP) can influence a physician's choice of drugs and dosages, as well as a patient's adherence to the medication. High-quality care requires patients to participate in medication decisions. This study aimed to compare perceived risks of medications and co-medications between physicians and persons living with CP.
View Article and Find Full Text PDFJ Med Chem
January 2025
Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, Copenhagen DK-2100, Denmark.
GABA receptors (GABARs) are the major elements of inhibitory neurotransmission in the central nervous system (CNS). They are established targets for regulation by endogenous brain neuroactive steroids (NASs) such as pregnanolone. However, the complexity of de novo synthesis of NAS derivatives has hindered attempts to circumvent the principal limitations of using endogenous NASs, including selectivity and limited oral bioavailability.
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